hall sensor

[let_nova]

might be noob question but what does it do?

rep left for info

[bazil]

duno if this is the same thing

http://www.bosch-motorsport.com/content/language2/html/2871.htm

or


http://en.wikipedia.org/wiki/Hall_effect

[mowgli]

abs sensors use the hall effect..

[MK999]

Measure the speed of various shafts, normally with a wheel with a tooth missing, it can detect the missing tooth from a voltage difference as it passes, through the Hall effect, hence the name.

edit: missing tooth will give you speed+position for crankshafts etc, abs ones just use speed so dont have a missing tooth I believe.

[Graeme]

Isn't it in the dizzy?

[bazil]

Isn't it in the dizzy?

my understanding then of a hall effect dizzy would be, it would get the engine speed from the camshaft? As it drives the dizzy shaft and it's speed is measured inside the dizzy body?

As my gte has a hall dizzy but no crank/cam sensor and dispack engines have crank sensor

Or am I getting it wrong?

[let_nova]

its on the LET on the dizzy. what is the purpose of it? if its unplugged it still starts etc.

[nova_saloon]

same with the XE, and later XE with coil pack. just the hall effect comes up as the cam sensor and you can unplug that and nothing happens

[gazsnova]

hall effect-
used on your ignition system. but the easiest way to explain how it works would be to use an abs sensor (which uses hall effect)

on an abs pickup ring there is several teeth which (when in rotation) passes close to the abs sensor.
this sensor uses an electromagnet which, when each of the teeth line up close to the sensor, the voltage increases. and as it moves away from the sensor the voltage drops. with many teeth on the pickup ring this would cause voltage fluctuations (if youve seen an oscilloscope you can read the sine wave it creates). the ecu can then interpret this information and use it to determine vehicle speed and compare it to the other abs sensors (usually to see which wheel locks up first on heavy braking and release that brake)

very similar theory to the type in the distributor and the ecu uses the information for ignition timing and advancement. could be uses for other thing specific to your engine (c20let) not sure though would have to research more.

hope this gives you a better understanding.

[let_nova]

ok i think i get that. if the hall sensor was "faulty" could it cause poor running?

[gazsnova]

yeah i would say so.

describing stuff like that is so much easier with pictures lmao.

[Tony M]

ok i think i get that. if the hall sensor was "faulty" could it cause poor running?

My ECU was picking up a problem with this sensor and it caused a very lumpy idle.